As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING ANNUAL INSPECTION IT WAS FOUND THAT ONE ALTERNATOR THROUGH BOLT HAD BROKEN OFF PART WAY UP THE THREAD AREA JUST OUTSIDE OF THE END FRAME CASTING. THIS SAME ALTERNATOR HAD ANOTHER BOLT FAIL AT APPROXIMATELY 10 HOURS. BOLTS REPLACED WITH OEM STOCK. WHEN THE BROKEN BOLT WAS DRILLED OUT, IT APPEARED TO BE QUITE SOFT.